A detailed methodological investigation into the determinants of migration in low-income countries is proposed. The project is concerned with estimating the determinants of geographic mobility for both households and individuals. The analysis will be carried out for Ecuador because of the availability of an unusually rich micro-level data set. These data will be merged with areal variables for purposes of empirical estimation. Comparisons of models typical of past empirical studies (based on more limited data) with our own will indicate the extent to which expanded models are desirable and previous models misspecified. Methodological improvements over previous work also include: 1. The incorporation of community and structural variables relating to community facilities and extra-familial economic conditions in household migration decision functions; 2. A structural equations approach to the understanding of the direct and indirect effects of contextual variables on migration decision-making; 3. The estimation of separate migration functions for the movement of entire households and individuals; 4. Comparison of the determinants of actual migration; and 5. Selective use of probit and logit estimation techniques.